Highest temperature in Guangzhou on July 20?

Platform comparison

Market context

Guangzhou is currently under a thick layer of overcast skies with high humidity, suppressing the daytime high to a forecasted 32°C despite it being peak summer. The crowd-implied 0% probability for any temperature above the current consensus reflects this immediate cloud cover and the 66% chance of precipitation expected later today, which historically acts as a strong thermal brake in the subtropical monsoon climate [8][10].

Historical data for mid-July in Guangzhou shows daytime maximums typically reaching 33°C, with long-term averages hovering between 27°C and 33°C during the hottest period of the year [2][7]. However, the market’s current pricing aligns with the specific 2026 forecast showing daily highs ranging from 88°F to 98°F (31°C–37°C), where the average high is 92°F (33°C) [1]. The 0% probability for higher ranges suggests traders are betting the current overcast conditions and rain will prevent the temperature from breaching the typical 33°C ceiling seen in comparable clear-sky July days [2].

Traders should monitor the afternoon thunderstorm probability, which sits at 16% and could drop the temperature further if heavy rain arrives [10]. The key dependency is the persistence of the 97% cloud cover, which blocks solar radiation and keeps the RealFeel temperature distinct from the actual air temperature [10]. Any sudden clearing of skies before the 12:00Z settlement window would be the primary catalyst for a rapid shift in probabilities, as clear July days in Guangzhou routinely exceed 33°C [2][4].

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We track Highest temperature in Guangzhou on July 20? across the five venues with material prediction-market liquidity. The probability shown is the live Polymarket mid; the comparison rows summarise how each venue treats the underlying contract — fees, KYC thresholds, settlement currency, deposit options. The highlighted row marks the cheapest route into Polymarket's order book.

Resolution & payout

Polymarket-based markets settle through the UMA Optimistic Oracle on Polygon. A proposer submits the outcome, a two-hour challenge window opens, and unchallenged proposals finalise the resolution. Payouts settle automatically in USDC the moment the result is final — no bookmaker, no delay.

Kalshi-based markets settle in USD via the CFTC-regulated clearinghouse. Betfair Exchange settles in GBP/EUR net of commission. Manifold is play-money and does not pay out real funds.

FAQ

How does resolution work?

Through the UMA Optimistic Oracle on Polygon: a proposer submits the outcome, a two-hour challenge window opens, and USDC payouts settle automatically once the result is final.

What's the difference between YES and NO shares?

A YES share pays $1.00 if the event happens, $0 otherwise. A NO share pays $1.00 if the event doesn't happen. The market price between 0¢ and 100¢ is the implied probability.

What does Polymarket cost to trade?

Polymarket itself charges 0% — the only cost is the Polygon network fee, typically under $0.01 per transaction. Off-chain venues like Kalshi or Betfair charge 2-7% commission.

How fast are USDC deposits?

Polygon credits deposits after 12 confirmations — usually under 30 seconds. Withdrawals follow the same path and land back in your wallet within minutes.

Do I need to KYC for this market?

On Polymarket directly, no — it's wallet-based. Intermediary brokers like Prediction Today trigger KYC only above $1,500 of lifetime trading volume; under that you trade pseudonymously with a single wallet address.